Students from a U.S. elementary school where a gunman killed 20 children and six staff members last month returned to class Thursday for the first time.

The December 14 massacre at Sandy Hook Elementary school in Newtown, Connecticut ended when the gunman committed suicide. That school remains closed, so students are attending a refurbished middle school in the neighboring town of Monroe that has been renamed Sandy Hook.

Monroe Police Lieutenant Keith White said Wednesday that authorities want the building to be a "normal school" that is not overburdened with police. But he said numerous security devices have been installed at the site.

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Sandy Hook Students Return to Class

"I think right now it has to be the safest school in America," White said.

Newtown Superintendent Janet Robinson said the plan is for the school to proceed with a regular schedule Thursday. When asked if there were plans to specifically address the shooting with students, she said kids that age "do not need to re-live that."

Parents and students toured the school Wednesday, and parents will be allowed to stay there Thursday if they choose. Extra mental health workers will also be at the school.

The rampage was the second-worst school shooting in U.S. history and brought renewed focus to the issue of gun control in the United States. President Barack Obama has asked Congress to reinstate a ban on assault weapons, and tasked Vice President Joe Biden to lead an effort to write a concrete set of proposals to address gun violence.